[If the name is Operator+++++, I corrected not optimized and not working code and added arcsin, arctan and arccos] It gets the distance from each pixel to both the circles, then runs it through the selected function. The options are d1 + d2, d1 - d2, d1 * d2, d1 / d2, d1 % d2, max(d1, d2), min(d1, d2), abs(d1-d2), sin(d1+d2), tan(d1+d2), cos(d1+d2), log(d1+d2), ln(d1+d2), sqrt(d1-d2), arcsin(min/max), arctan(d1/d2), cos(min/max)